| The body weight, shank length and chest bone length were measured from birth to 12 weeks in 235 New Yangzhou chickens. Two hundred and twenty of the chickens were slaughtered at 12-week, and the carcass, semi-eviscerated, eviscerated, chest muscle, leg muscle, head, feet, heart, liver, spleen, stomach, gland stomach weights, small intestine length, pH in chest muscle and cut strength in chest muscle were measured. Dressing, semi-eviscerated, eviscerated, chest muscle and leg muscle percentages were calculated based on above carcass traits. The body weight, shank and chest bone lengths, heart, liver, spleen, yolk sac weights and small intestine length were measured at birth in 195 New Yangzhou chickens. The 195 chickens at birth, 220 chickens and 43-adult cocks were typed for 10 protein and 20 microsatellite loci, respectively! The growth of New Yangzhou chickens were simulated by Gompertz, Logistic and Bertalanffy Models. Heritabilities of growth, carcass and meat quality traits were calculated with Restricted Maximum Likelihood Method (RMLM) and molecular-marker-based approach (MMBA). The allele frequencies, effective number of alleles, heterozygosity(H), heterozygote frequencies, polymorphism information content (PIC) and individual heterozygosity were determined. The association between individual heterozygosity and each trait mentioned above were analyzed and the differences of the traits among individual heterozygosity levels were compared. The results were as follows:I Growth of New Yangzhou ChickenThe body weight of New Yangzhou chicken at 12-week was 1144.30 g, which was bigger in cocks than in hens (1295.34 vs. 1024.18, p < 0.01). The body weight growth curve was S-shape, which could be simulated by Gompertz Model (R~2 > 0.99). The simulated age at inflexion was 8 week and body weight at inflexion was 780 g in cocks. The simulated age at inflexion was 7-week and body weight at inflexion was 588 g in hens.The shank length of New Yangzhou chickens at 12-week was 7.88 cm, which was bigger incocks than in hens (8.34 vs. 7.51, p < 0.01). The shank length growth curve was S-shaped, which could be simulated by Logistic Model (R2 > 0.99). The simulated age at inflexion was 4 week and shank length at inflexion was 4.7 cm in cocks. The simulated age at inflexion was 3.5-week and shank length at inflexion was 4 cm in hens.The chest bone length of New Yangzhou chickens at 12-week was 10.03 cm, which was bigger in cocks than in hens (10.50 vs. 9.65, p < 0.01). The chest bone length growth curve was similar to the afore-mentioned shape, which could be simulated by Bertalanffy Model (R2 > 0.98). The simulated age at inflexion was 1.5-week and chest bone length at inflexion was 3.8 cm in cocks. The simulated age at inflexion was 1.2-week and chest bone length at inflexion was 3.5 cm in hens.The heritabilities of body weight by REMLMT from birth to 12-week were 0.416-0.697, which of shank length were 0.246-0.553, and which of chest bone length were 0.225-0.416.The values of heritabilities of body weight with molecular markers were smaller than those with RML.II Carcass and meat quality traits of New Yangzhou ChickensThe carcass, semi-eviscerated, eviscerated, chest muscle, leg muscle, head, feet, heart, liver, spleen, stomach, gland stomach weights, small intestine length, pH in chest muscle and cut strength in chest muscle were 1015.22 g, 932.36 g, 786.94 g, 66.47 g, 85.26 g, 36.75 g, 43.30 g, 4.41 g, 22.40 g, 1.35 g, 30.01 g, 3.70 g, 115.53 cm, 6.25, 3.87, respectively. Most of these carcass traits were bigger in cocks than in hens (p < 0.01).The heritabilities of carcass, semi-eviscerated, eviscerated, chest muscle, leg muscle weights were 0.437-0.630, and the head, feet, heart, liver, stomach and gland stomach weights were 0.142-0.251.III Genetic structure of New Yangzhou ChickensThe effective number of alleles of the 30 loci in New Yangzhou Chickens was 1-4. A total of 25 alleles were observed at protein loci. And the mean H and PIC of which were 0.47 and 0.35, respectively. A total of 71 alleles were observed at microsat...
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